A compound X made of two non-metals in a reaction with another non-metal Y gives the hardest substance and carbon monoxide. Identify the compound X and the non-metal Y.

Options

A. `CO_2, Si`
B. `SiO_2, C`
C. `SiC, O_2`
D. CO, Si

Answer

To solve the problem, let's break it down step by step.

### Step 1: Identify the Hardest Substance
The question states that the reaction produces the hardest substance. The hardest naturally occurring substance on Earth is diamond.

### Step 2: Understand the Composition of Diamond
Diamond is an allotrope of carbon, which means it is a different structural form of the same element. Therefore, one of the non-metals involved in the reaction must be carbon (C).

### Step 3: Identify Compound X
The question mentions that compound X is made of two non-metals. Since we have identified carbon as one of the non-metals, we need to find another non-metal that can combine with carbon to form a compound.

A common compound of carbon and silicon is silicon carbide (SiC), which is known for its hardness and is used in various industrial applications.

### Step 4: Identify Non-metal Y
In this reaction, we need to identify the second non-metal (Y) that reacts with compound X (SiC) to produce diamond and carbon monoxide (CO). Since we have already established that carbon is involved, we can conclude that the other non-metal Y is silicon (Si).

### Step 5: Write the Reaction
The reaction can be summarized as follows:
- When silicon (Si) reacts with carbon (C) in silicon carbide (SiC), it produces diamond (the hardest substance) and carbon monoxide (CO).

### Conclusion
Thus, the compound X is silicon carbide (SiC) and the non-metal Y is silicon (Si).

### Final Answer:
- Compound X: Silicon Carbide (SiC)
- Non-metal Y: Silicon (Si)

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